In the process of long-distance pipeline jacking, especially while encountering complex stratum such as sand and gravel layer, aimed at the problems of strata collapse or jacking failure caused by excessive increase of pipe jacking resistance, a study on the clay-free slurry′s lubricating and resistance-reducing wall-protecting properties has been carried out with plant gum and polymer as its main materials. Finally, an optimum formula of clay-free slurry is obtained for long-distance pipeline jacking engineering by orthogonal experiment.